Orbital Conducts 100th Consecutive Successful Space Mission Since 1997

The successful execution of three
separate space missions during the past week has propelled Orbital Sciences
Corporation to a major operational milestone — the completion of
100 consecutive successful space missions over the past 50 months — the
company stated today.
Since January 1997, Orbital’s wide variety of space
technology products have established a track record of outstanding
reliability, with an impressive series of 45 satellite deployments, 36 rocket
launches, 14 robotics missions and 5 space sensor and other payloads
successfully launched, deployed and operated during this period.
Since the
mid-1990’s, Orbital has been among the most operationally active and
successful space companies in the world.

“It is a great source of pride to all of us at Orbital to be an innovative
and dependable supplier of some of the industry’s most reliable space
technology products,” said Mr. David W. Thompson, Orbital’s Chairman and Chief
Executive Officer.
“With numerous other space missions on the 2001 calendar,
we are looking forward to extending this extraordinary ‘winning streak’ for
our customers even further this year.”

The three missions recently carried out include two space robotics systems
produced by the company’s Ontario, Canada-based MD Robotics division.
The
“Canadarm” Remote Manipulator System was used aboard the Space Shuttle’s
current mission to support extensive extra-vehicular activities by the
astronaut crew to further assemble the International Space Station (ISS) and
prepare it for long-term habitation.

In addition, the Robotic Work Station payload was installed in the U.S.
Destiny module on the ISS.
It will serve as the astronaut crew’s control
station for the ISS’ new external robotics system, which is also built by MD
Robotics.
This new advanced robotics system will be launched and installed on
another Space Shuttle mission currently scheduled in April.

Orbital also deployed a new geostationary communications satellite for
Japan’s Broadcasting Satellite System Corporation (B-SAT).
The BSAT-2a
satellite was launched into orbit on March 8 aboard an Ariane 5 rocket.
The
initial in-orbit checkout of the spacecraft has been fully successful, with
all data indicating that the satellite is operating as expected.
Over the
next several weeks, after a more extensive series of tests are performed, the
BSAT-2a satellite will be moved to its final orbital position at 110 degrees
East longitude and will be delivered to B-SAT for initiation of television
broadcast services in Japan.

‘Orbital is one of the world’s leading manufacturers of low-cost space
systems, including satellites, launch vehicles, space sensors and satellite
ground systems. Its Magellan subsidiary offers the industry’s broadest line of
GPS-enabled navigation and positioning products for consumer and industrial
markets. Through its relationships with ORBCOMM, ORBIMAGE and ORBNAV, Orbital
is also involved with satellite-based networks that provide data
communications, high-resolution imagery and automotive information services to
customers around the world.

More information about Orbital can be found at http://www.orbital.com .

CONTACT:
Investors: Timothy Perrott of Orbital Sciences Corporation,
703-406-5997, or perrott.tim@orbital.com.